With devices for dividing vector forces into their components it is very difficult to achieve a division without an interaction at high accuracy since all measures taken for an interaction-free division are accompanied by other affects as friction which affect the accuracy of measurement. Mechanical devices are complicated and voluminous in design. Piezoelectric devices are relatively inaccurate, temperature-sensitive and not applicable for static measurements even in a range of a few seconds.
The U.S. Pat. No. 4,112,752 discloses a force measuring apparatus for measuring the forces of a flowing medium, such as air flow in a wind tunnel, acting on an object where aerodynamic properties are to be investigated. The object is secured to an object carrier which is mounted in a bearing system permitting movement in the directions of the force components in vertical and mutually perpendicular horizontal directions, the object carrier being connected to a force measuring device in each of these directions. The object carrier is supported by hydrostatic bearings so as to be moveable in the directions of the force components to be measured. As force measuring devices strain gauge devices are used. There are three support and guiding means of complex design where one support and guiding means is inserted into the other. Thus, the design is rather complex and expensive.